1. Field of the Invention
The present invention relates to a semi-cured product, a cured product and a method of manufacturing the same, an optical component, and a curable resin composition.
2. Background Art
An imaging module has been used for a camera, a video camera, a mobile phone with a camera, a video phone, or a door phone with a camera. In recent years, particularly miniaturization has been demanded in an optical system used for the imaging module. When the optical system is miniaturized, chromatic aberration of the optical system may become a big problem.
In the related art, glass which is used as a material of the optical system can realize various optical characteristics to be demanded and has excellent environmental resistance, but there is a problem in that workability thereof is degraded. In contrast, a synthetic resin is low in cost when compared to a glass material and has excellent workability, but there is a problem in that heat resistance thereof is degraded when compared to the glass material.
A method of changing characteristics after curing by adding various additives to a photo-curable resin composition has been known. For example, Patent Literature 1 discloses an aspect of using a curable resin composition which has 0.5 parts by mass to 30 parts by mass of a monofunctional acryl, a difunctional acryl, and a terpene compound with respect to acryls, and to which a photo-polymerization initiator is added as a resin composition for coating of an alicyclic structure-containing polymer (COP) molded body and a COP protection coating material. The same literature discloses that a resin obtained by polymerizing a terpene compound for improving adhesion with COP can be used. However, the above-described composition has insufficient heat resistance.
Patent Literature 2 discloses an example of adding an alicyclic radical polymerizable group-containing compound (A), a photo-polymerization initiator and a thermal polymerization initiator (B), and a difunctional radical polymerizable compound (A′) in Example 6, and performing photo-polymerization and thermal polymerization in this order. The same literature discloses that a fine shaping property of a curable resin composition can be resolved with such a configuration. However, the above-described composition has an insufficient shaping property from a viewpoint of use for an optical component such as a heat-resistant lens.
In recent years, it has been known that chromatic aberration can be corrected by decreasing a high refractive index and the Abbe's number of a material composition to have a high dispersion property (for example, Patent Literatures 3 and 4). Patent Literature 3 discloses that an optical element having a high refractive index, a high dispersion property, and excellent heat resistance can be obtained from a material composition containing a compound of acryloyloxyalkyl carbazole or methacryloyloxyalkyl carbazole and a polymerizable compound having at least one structure selected from a biphenyl structure, a bisphenol A structure, a fluorene structure, and a naphthalene structure in a molecule. Patent Literature 4 discloses that a composite optical element formed of only a resin which is effective for decreasing the chromatic aberration and other aberrations can be obtained from a composition containing a compound of carbazole having a vinyl group, a vinylidene group, a vinylene group, an acryloyl group, and a methacryloyl group as a polymerizable functional group; a polymerizable group which has one to three polymerizable functional groups and whose functional groups are a vinyl group, an acrylic group, or a methacrylic group; and a polymerization initiator.